Hi Robert,
Not sure of the specific issue and or age of your truck, but Combilift have a dedicated Technical Team covering the UK. If you still need support, you can complete a quick technical support form at the bottom of the main combilift.com web site or direct link https://warranty.combilift.net/technical-support-form/. The form only asks for the minimal info so the team can quickly help you. There is no login required and no charge for this support.
The Uk Team will be back to you quickly. Hope you get sorted quickly.